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On another forum, there is a post showing the use of an Arduino Pro Mini as a servo exerciser. A question was then asked if it could be modified to operate as a servo reverser or a servo slow. Another question was then asked if a switch output could be added so that, for example, if flaps were lowered, the switch could then turn on landing lights.

So, I've put together some Arduino code to do all three!
It is here on Github: https://github.com/MikeBland/ServoReverser.

It takes a single channel input, and outputs the same pulse but reversed on one output, the pulse slowed on a second output and a logic output that switches based on the input pulse value.

There are some #defines at the top of the file to configure the operation.
You may reverse the slow output.
You may set the end to end time for the slowed output.
You may choose whether the logic output switches high or low.
You may set the point on the input pulse where the switch activates.
You may set some hysteresis so the switch doesn't "jitter" if the input pulse is hovering around the switching point.

No doubt other functions could be added, a door sequencer was mentioned!

Mike

Thanks Mike, this is really cool.

A couple years ago, me and another forum member started working on something similar, never finished it though
It was for radios that have not so many channels, or for bigger models that need many channels.
it was kind of a programmable channel doubler.
Imagine for example a plane that uses one servo for each aileron, but you need one of the channels for controlling something else.
An arduino could be used to control the second aileron servo, and the configuration would be done on the arduino. Or, it would receive a plain -100% to 100% signal, and it would output the 2( or more) aileron servo signals. Configuration (reverse, end points, etc) would be done using a couple pushbuttons at startup, and then stored in the eeprom.
I have a commercial system that does this in my big scale Tony Clark Piper J3 Cub, powered by a 62CC petrol engine. It needs quite a few channels and it doubles the input channels with independent settings. I never saw a DIY project that did this or similar. So we started, but somehow we lost contact and never finished it..

João